Liquid crystal display and the backlight module thereof

Abstract

An LCD and the backlight module thereof is provided. The backlight module includes a printed circuit board, a first light source, a first signal-modulating device, and a second light source. The first signal-modulating device is disposed on the printed circuit board and is electrically connected to the first light source. The first light source is adjusted through the first signal-modulating device to generate light with substantially the same luminance as that of the second light source with different luminance characteristics, so that the backlight module achieves uniform luminance.

1 . A backlight module, comprising: 
 a first printed circuit board;    a first light source, being disposed on the first printed circuit board;    a first inverter, being disposed the first printed circuit board for driving the first light source; and    a first signal-modulating device, being disposed on the first printed circuit board, and electrically connected to the first inverter, the luminance of the first light source being adjusted by modulating the first signal-modulating device.    
   
   
       2 . The backlight module according to  claim 1 , wherein the first signal-modulating device is a first adjustable resistor.  
   
   
       3 . The backlight module according to  claim 2 , wherein the first inverter is serially connected with the first adjustable resistor, the first inverter outputs a first current for driving the first light source, the strength of the first current is related to the resistance of the first adjustable resistor.  
   
   
       4 . The backlight module according to  claim 1 , wherein the first light source is disposed on a first surface of the first printed circuit board, while the first inverter and the first signal-modulating device are also disposed on the first surface.  
   
   
       5 . The backlight module according to  claim 1 , wherein the first light source is disposed on a first surface of the first printed circuit board while the first inverter and the first signal-modulating device are disposed on the second surface, wherein the first surface is opposite to the second surface.  
   
   
       6 . The backlight module according to  claim 1 , wherein one side of the first printed circuit board has a connector, the connector is electrically connected to the first inverter, the first printed circuit board is electrically connected to an external circuit through the connector.  
   
   
       7 . The backlight module according to  claim 1 , wherein the backlight module further comprise a second light source, a second inverter and a second signal-modulating device, the second light source is disposed on the first printed circuit board, the second inverter is disposed on the first printed circuit board for driving the second light source, the second signal-modulating device is disposed on the first printed circuit board and is electrically connected to the second inverter, through modulating the resistance of the second signal-modulating device, the luminance of the second light source can be adjusted so that the luminance of the first light source and the luminance of the second light source are substantially identical.  
   
   
       8 . The backlight module according to  claim 7 , wherein the second signal-modulating device is a second adjustable resistor.  
   
   
       9 . The backlight module according to  claim 8 , wherein the second inverter, which is serially connected to the second adjustable resistor, outputs a second current, whose strength is related to the resistance of the second adjustable resistor, for driving the second light source, at least one of the first inverter and the second inverter is disposed between the first light source and the second light source, through modulating the resistance of the first adjustable resistor and the luminance of the second adjustable resistor, the first light source and the second light source, whose luminance characteristics are different, generate substantially identical luminance.  
   
   
       10 . The backlight module according to  claim 9 , wherein the first light source and the second light source is a cold cathode fluorescent lamp (CCFL) or a hot cathode fluorescent lamp.  
   
   
       11 . The backlight module according to  claim 1 , wherein the backlight module further comprise a second light source, a second printed circuit board, a second inverter, a second signal-modulating device and a light guide panel, the second light source is disposed on the second printed circuit board, the second inverter is disposed on the second printed circuit board for driving the second light source, while the second signal-modulating device is disposed on the second printed circuit board and is electrically connected to the second inverter, the first light source and the second light source are disposed at the two sides of the light guide panel, through modulating the resistance of the second signal-modulating device, the luminance of the second light source can be adjusted so that the luminance of the first light source and the luminance of the second light source are substantially identical.  
   
   
       12 . A liquid crystal display (LCD), comprising: 
 a display housing, having an receiving space;    a first signal-socket, being disposed within the receiving space for providing a first driving signal; and    a backlight module, being removeably disposed within the receiving space, comprising:    a first printed circuit board, being selectively electrically connected to the first signal-socket for receiving the first driving signal;    a first light source, being disposed on the first printed circuit board and driven by the first driving signal; and    a first signal-modulating device, being disposed on the first printed circuit board and electrically coupled to the first light source, through modulating the first driving signal passing through the first signal-modulating device, the luminance of the first light source being adjusted.    
   
   
       13 . The LCD according to  claim 12 , wherein the backlight module further comprises a second light source and a second signal-modulating device, the second light source is disposed on the first printed circuit board, while the second signal-modulating device is disposed on the first printed circuit board and is electrically connected to the second light source, the first signal-socket further provides a second driving signal to the first printed circuit board, through modulating the second signal-modulating device, the luminance of the second light source can be changed so that the luminance of the first light source and the luminance of the second light source are substantially identical.  
   
   
       14 . The LCD according to  claim 13 , wherein the first signal-modulating device is a first adjustable resistor, while the second signal-modulating device is a second adjustable resistor.  
   
   
       15 . The LCD according to  claim 13 , wherein the strength of first driving current is related to the resistance of the first adjustable resistor, the strength of the second driving current is related to the resistance of the second adjustable resistor, through modulating the resistance of the first adjustable resistor and that of the second adjustable resistor, the first light source and the second light source, whose luminance characteristics are different, generate substantially identical luminance.  
   
   
       16 . The LCD according to  claim 13 , wherein the first light source and the second light source are disposed on a first surface of the first printed circuit board, while the first adjustable resistor and the second adjustable resistor are also disposed on the first surface, at least one of the first adjustable resistor and the second adjustable resistor is disposed between the first light source and the second light source.  
   
   
       17 . The LCD according to  claim 13 , wherein the first light source and the second light source are disposed on a first surface of the first printed circuit board while the first adjustable resistor and the second adjustable resistor are disposed on a second surface, the first surface is opposite to the second surface.  
   
   
       18 . The LCD according to  claim 13 , wherein the first light source and the second light source are light emitter diode (LEDs).  
   
   
       19 . The LCD according to  claim 13 , wherein the LCD further comprises a first control printed circuit board for controlling the LCD panel, the first control printed circuit board has a first inverter and a second inverter, which respectively generates the first driving signal and the second driving signal.  
   
   
       20 . The LCD according to  claim 19 , wherein the first light source and the second light source is either a CCFL or a hot cathode fluorescent lamp.  
   
   
       21 . The LCD according to  claim 12 , wherein the backlight module further comprises a second light source, a second printed circuit board, a second signal-modulating device, a light guide panel and a second signal-socket, the second light source is disposed the second printed circuit board, while the second signal-modulating device is disposed on the second printed circuit board and is electrically connected to the second light source, the second signal-socket further provides a second driving signal to the second printed circuit board, the first light source and the second light source are disposed at the two sides of the light guide panel, through modulating the second signal-modulating device, the luminance of the second light source can be changed so that the luminance of the first light source and the luminance of the second light source are substantially identical.